Active Damping and Energy Recovery in a Hydraulic Boom Controlled by an Electric Drive

The aim of the study is to obtain a mathematical description for an alternative variant of controlling a hydraulic circuit with an electrical drive. The electrical and hydraulic systems are described by basic mathematical equations. The flexibilities of the load and boom is modeled with assumed mode method. The model is achieved and proven with simulations. The controller is constructed and proven to decrease oscillations and improve the dynamic response of the system.

How much protein and energy are needed to equilibrate nitrogen and energy balances in ventilated critically ill children?

BACKGROUND & AIMS: Protein and energy requirements in critically ill children are currently based on insufficient data. Moreover, longitudinal measurements of both total urinary nitrogen (TUN) and resting energy expenditure (REE) are lacking. The aim of this study was to investigate how much protein and energy are needed to equilibrate nitrogen and energy balances in ventilated critically ill children on the basis of daily measurements of TUN, REE and protein and energy intakes. Comparisons were made with the guidelines of the American Society for Parenteral and Enteral Nutrition and the Dietary Reference Intakes. METHODS: Children with an expected duration of mechanical ventilation ≥72 h were prospectively recruited. TUN was measured by chemiluminescence, and REE was measured by indirect calorimetry. Generalised linear models for longitudinal data were used to study the relation between protein intake and nitrogen balance and to calculate the minimum intake of protein needed to achieve nitrogen equilibrium. A similar approach was used for energy. Results were compared to the recommended values. RESULTS: Based on 402 measurements performed in 74 children (median age: 21 months), the mean TUN was high at 0.20 (95% CI: 0.20, 0.22) g/kg/d and the REE was 55 (95% CI: 54, 57) kcal/kg/d. Nitrogen and energy balances were achieved with 1.5 (95% CI: 1.4, 1.6) g/kg/d of protein and 58 (95% CI: 53, 63) kcal/kg/d for the entire group, but there were differences among children of different ages. Children required more protein and less energy than the Dietary Reference Intakes. CONCLUSIONS: In critically ill children, TUN was elevated and REE was reduced during the entire period of mechanical ventilation. Minimum intakes of 1.5 g/kg/d of protein and 58 kcal/kg/d can equilibrate nitrogen and energy balances in children up to 4 years old. Older children require more protein.

Chemistry and light - part 2: light and energy

The conversion of solar energy into more useful forms of energy, such as chemical fuels or electricity, is one of the central problems facing modern science. Progress in photochemistry and chemical synthesis has led to a point where light energy conversion by means of artificial molecular devices can be rationally attempted. In this article, a general approach towards this challenging goal is presented.

On Value Creation at an Industrial Intersection – Bioenergy in the Forest and Energy Sectors

The traditional forest industry is a good example of the changing nature of the competitive environment in many industries. Faced with drastic challenges forestindustry companies are forced to search for new value-creating strategies in order to create competitive advantage. The emerging bioenergy business is now offering promising avenues for value creation for both the forest and energy sectors because of their complementary resources and knowledge with respect to bioenergy production from forest-based biomass. The key objective of this dissertation is to examine the sources of sustainable competitive advantage and the value-creation opportunities that are emerging at the intersection between the forest and energy industries. The research topic is considered from different perspectives in order to provide a comprehensive view of the phenomenon. The study discusses the business opportunities that are related to producing bioenergy from forest-based biomass, and sheds light on the greatest challenges and threats influencing the success of collaboration between the forest and energy sectors. In addition, it identifies existing and potential bioenergy actors, and considers the resources and capabilities needed in order to prosper in the bioenergy field. The value-creation perspective is founded on strategic management accounting, the theoretical frameworks are adopted from the field of strategic management, and the future aspect is taken into account through the application of futures studies research methodology. This thesis consists of two parts. The first part provides a synthesis of the overall dissertation, and the second part comprises four complementary research papers. There search setting is explorative in nature, and both qualitative and quantitative research methods are used. As a result, the thesis lays the foundation for non-technological studies on bioenergy. It gives an example of how to study new value-creation opportunities at an industrial intersection, and discusses the main determinants affecting the value-creation process. In order to accomplish these objectives the phenomenon of value creation at the intersection between the forest and energy industries is theorized and connected with the dynamic resource-based view of the firm.

Material embodiment and energy flows as efficiency indicators of soybean (Glycine max) production in Brazil

As the requirement for agriculture to be environmentally suitable there is a necessity to adopt indicators and methodologies approaching sustainability. In Brazil, biodiesel addition into diesel is mandatory and soybean oil is its main source. The material embodiment determines the convergence of inputs into the crop. Moreover, the material flows are necessary for any environmental analysis. This study evaluated distinct production scenarios, and also conventional versus GMO crops, through the material embodiment and energy analysis. GMO crops demanded less indirectly applied inputs. The energy balance showed linearity with yield, whereas for EROI, the increases in input and yield were not affected.

Impact of irrigation on yield and energy balance of the production of oil and cake of two sunflower varieties

The energy balance for the production of sunflower oil and cake was carried out during the agricultural and industrial stage phase, where it was considered a cold extraction by hydraulic pressing, with the plant location in a rural area with a radius of 30km range. Data on productivity was used in two varieties of sunflower (Helio 358 and Aguará 04) grown in different seasons (2007/2008, 2008/2009), under different irrigation levels. Data showed that irrigation resulted in an increase in productivity of both varieties, and the best response was observed for Aguará 04 variety. Moreover, the increased intensity of irrigation negatively affected the energy balance, reducing the ratio between energy produced and energy used in the production chain. The most significant inputs in the energy intake were fertilizer followed by diesel oil, when irrigation was not used for. When the irrigation technique was used, the most significant inputs, in order of representativeness, were: energy, fertilizer and equipment.

Belt conveyor energy efficiency analysis and energy model development

An energy model of a belt conveyor was designed. Operation of a belt conveyor was researched. Operational indexes were calculated. Energy optimization process and recommendations were presented.

Volume and energy folding landscape of prion protein revealed by pressure

The main hypothesis for prion diseases proposes that the cellular protein (PrP C) can be altered into a misfolded, ß-sheet-rich isoform, the PrP Sc (from scrapie). The formation of this abnormal isoform then triggers the transmissible spongiform encephalopathies. Here, we discuss the use of high pressure as a tool to investigate this structural transition and to populate possible intermediates in the folding/unfolding pathway of the prion protein. The latest findings on the application of high pressure to the cellular prion protein and to the scrapie PrP forms will be summarized in this review, which focuses on the energetic and volumetric properties of prion folding and conversion.

Early detection of metabolic and energy disorders by thermal time series stochastic complexity analysis

Maintenance of thermal homeostasis in rats fed a high-fat diet (HFD) is associated with changes in their thermal balance. The thermodynamic relationship between heat dissipation and energy storage is altered by the ingestion of high-energy diet content. Observation of thermal registers of core temperature behavior, in humans and rodents, permits identification of some characteristics of time series, such as autoreference and stationarity that fit adequately to a stochastic analysis. To identify this change, we used, for the first time, a stochastic autoregressive model, the concepts of which match those associated with physiological systems involved and applied in male HFD rats compared with their appropriate standard food intake age-matched male controls (n=7 per group). By analyzing a recorded temperature time series, we were able to identify when thermal homeostasis would be affected by a new diet. The autoregressive time series model (AR model) was used to predict the occurrence of thermal homeostasis, and this model proved to be very effective in distinguishing such a physiological disorder. Thus, we infer from the results of our study that maximum entropy distribution as a means for stochastic characterization of temperature time series registers may be established as an important and early tool to aid in the diagnosis and prevention of metabolic diseases due to their ability to detect small variations in thermal profile.

Invoice process analysis and development. Case: Power and automation technology company

This master’s thesis studies the case company’s current purchase invoice process and the challenges that are related to it. Like most of other master’s thesis this study consists of both theoretical- and empirical parts. The purpose of this work is to combine theoretical and empirical parts together so that the theoretical part brings value to the empirical case study. The case company’s main business is frequency converters for both low voltage AC & DC drives and medium voltage AC Drives which are used across all industries and applications. The main focus of this study is on the current invoice process modelling. When modelling the existing process with discipline and care, current challenges can be understood better. Empirical study relays heavily on interviews and existing, yet fragmented, data. This, along with own calculations and analysis, creates the foundation for the empirical part of this master’s thesis.

Iron enriched Saccharomyces cerevisiae maintains its fermenting power and bakery properties

Iron is an essential micronutrient in the metabolism of almost all living organisms; however, its deficiency is well documented especially in pregnant women and in children. Iron salts as a dietary supplement have low bioavailability and can cause gastrointestinal discomforts. Iron enriched yeasts can provide a supplementation of this micronutrient to the diet because this mineral has a better bioavailability when bonded to yeast cell macromolecules. These yeasts can be used as feed supplement for human and animals and also as baker's yeast. Baker's yeast Saccharomyces cerevisiae was cultivated in a reactor employing yeast media supplemented with 497 mg ferrous sulfate.L-1, and the resultant biomass incorporated 8 mg Fe.g-1 dry matter. This biomass maintained its fermenting power regarding both water displace measurement through carbonic dioxide production and bakery characteristics. The bread produced using the yeast obtained by cultivation in yeast media supplemented with iron presented six times more iron than the bread produced using the yeast obtained by cultivation without iron supplementation.

Niagara Falls power and American industries /

Reprinted from the Transactions of the American Electrochemical Society, twenty-ninth general meeting, Washington, D.C., April 27-29, 1916.

A Foucauldian Analysis of Power and Representation in an Attempt to Run a Photovoice Project with Youth

This project evolved out of a search for ways to conduct research on “others” in a way that does not exploit, stigmatize or misrepresent their experience. This thesis is an ethnographic study in leisure research and youth work and an experiment in running a photovoice project. Photovoice is a participatory visual method that embodies the emancipatory ideal of empowering others through self-representation. The literature on photovoice lacks a comprehensive discussion on the complexity of power and representation. Postmodern theorists have proposed that participatory methods are not benign and that initiatives are acts of power in themselves that produce effects (Cook & Kothari, 2001). A Foucauldian analysis of power is used to deconstruct the researcher’s practice and reflect on why and how youth are “engaged”. This project seeks to embrace the principle of working “with” others, but also work from a postmodern perspective that acknowledges power and representation as ongoing problems.

Whose Voice Is Present?: An Examination of Power and Privilege in Service-Learning in Ontario Universities

This research paper examines themes of power and privilege that occur within service-learning as described by 3 Ontario universities on their service-learning websites. Due to size and time restrictions, this paper was able to examine only 3 Ontario universities: Brock, Wilfrid Laurier, and Lakehead. The purpose of this study is geared towards service-learning practitioners in order for the universities and students to become more self-aware of their immense place of privilege within the service-learning context. Qualitative narrative analysis research methods were employed in this purposeful sample to examine how each university’s story of service-learning reflected themes of power and privilege. The research found that each university posed a unique narrative of service-learning representing various stakeholders’ voices and presence in different ways on their website. Brock largely focuses on faculty and student voices. Laurier intentionally attempts to include all three stakeholder voices, although still favours students and the university as an audience over the community. Lakehead’s unique program includes a plethora of voices and intends much of their information for the community members, students, and the university. The implications of this research demonstrate that universities have a large amount of power and privilege, which is carried through to the students within the service-learning partnership.

University Faculty Members’ Understanding of Their Role: Identity, Power, and Silence

This qualitative study was conducted to explore tenured faculty members’ understandings of their roles as professors. Tenure is an institutional means to enact academic freedom, which allows tenured faculty members to investigate topics of their choosing free from external influence. Academic freedom also enables faculty members to be public intellectuals who shape and critique social policies and make knowledge assertions. In effect, the faculty members are institutionally protected to speak truth to power. Purposeful sampling of 9 participants from 2 universities yielded 3 major themes: professorial identity (shaped by such factors as career stage, university culture, and faculty affiliation), professorial power (powers that participants experienced as well as the ways in which they exercised power), and professorial silencing (as a response to fiscal realities coupled with numerous governance issues). While participants were cognizant of the powers that affected their freedoms, they were less aware of the ways in which their position afforded them powers. Subtle but more potent forms of power were at play for tenured professors, but the participants saw themselves as having to work within institutional and financial constraints that limited their freedom to speak out on controversial issues. Faculty members were, thus, silenced and at times chose to self-silence. The context of the present-day university, governance models, and the financial issues affecting universities and departments worked in concert to silence this critical voice in society.